[Feature Request]: Mode that throttles messages after /joining a channel

[Jigsy1]

What with the recent "freenodegate" spam attack - which is still ongoing I believe - would it be possible to include a channel mode which prevents a user from saying anything in a channel unless they've been in it for more than X seconds?

Using +J as an example (since I'm not sure what letters are already in use): /mode #chan +J 120 - means that they need to be in #chan for 120 seconds before they can speak otherwise the message is discarded.

This would most likely require caching the Unix Epoch of the time the user joined a channel then comparing it against the current epoch.

[edk0]

This isn't technically hard (though it's operationally tedious for freenode because it would require restarting ircd) but I don't think it would do much good against spam—it's too easy to just configure the bots to wait out the delay.

With that said, it might be a feature we want, but I hope this'll serve as an explanation of why there hasn't been any activity on this issue.